add domain creation form and model code

- implement domains.forms.CreateHostingDomainForm
- implement domains.models.HostingDomainManager.create_for_hosting_package that
  takes care of creating the necessary database objects for hosting domains
  assigned to a hosting package

gnuviechadmin/domains/models.py

@@ -4,7 +4,7 @@ This module contains models related to domain names.
 """
 from __future__ import absolute_import, unicode_literals
 
-from django.db import models
+from django.db import models, transaction
 from django.conf import settings
 from django.utils.encoding import python_2_unicode_compatible
 from django.utils.translation import ugettext as _
@@ -54,6 +54,27 @@ class MailDomain(DomainBase):
     mailaddresses = property(get_mailaddresses)
 
 
+class HostingDomainManager(models.Manager):
+    """
+    Default Manager for :py:class:`HostingDomain`.
+
+    """
+    @transaction.atomic
+    def create_for_hosting_package(
+        self, hosting_package, domain, commit, **kwargs
+    ):
+        from hostingpackages.models import CustomerHostingPackageDomain
+        hostingdomain = self.create(
+            customer=hosting_package.customer, domain=domain, **kwargs)
+        hostingdomain.maildomain = MailDomain.objects.create(
+            customer=hosting_package.customer, domain=domain)
+        custdomain = CustomerHostingPackageDomain.objects.create(
+            hosting_package=hosting_package, domain=hostingdomain)
+        if commit:
+            hostingdomain.save()
+            custdomain.save()
+        return hostingdomain
+
 
 @python_2_unicode_compatible
 class HostingDomain(DomainBase):
@@ -67,6 +88,8 @@ class HostingDomain(DomainBase):
         help_text=_('assigned mail domain for this domain')
     )
 
+    objects = HostingDomainManager()
+
     class Meta:
         verbose_name = _('Hosting domain')
         verbose_name_plural = _('Hosting domains')